(沈陽(yáng)工業(yè)大學(xué) 材料科學(xué)與工程學(xué)院， 沈陽(yáng) 110023)
摘 要: 根據(jù)分子動(dòng)力學(xué)理論建立液態(tài)ZA27合金的原子集團(tuán)， 結(jié)合計(jì)算機(jī)編程構(gòu)造出ZA27合金α相與液相共存時(shí)的原子構(gòu)形及α相大角度重位點(diǎn)陣晶界模型。 利用遞歸法計(jì)算鐵、 稀土元素固溶于晶粒內(nèi)、游離于固液相界面及其在α相晶界處的環(huán)境敏感鑲嵌能。結(jié)果表明： 鐵、 稀土處于固液相界區(qū)比在晶內(nèi)更穩(wěn)定， 這解釋了鐵、 稀土在α相內(nèi)溶解度很小， 結(jié)晶時(shí)富集于固液相界前沿液體中， 從而導(dǎo)致凝固結(jié)束后鐵、 稀土元素偏聚于晶界，并形成成分復(fù)雜的稀土化合物的事實(shí)。
關(guān)鍵字: 稀土; 晶界; 遞歸方法; 電子結(jié)構(gòu)
（College of Materials Science and Engineering，
Shenyang University of Technology， Shenyang 110023， China）
Abstract: A model of liquid ZA27 casted alloy was established according to molecular dynamics. An atomic structural model of α phase and liquid co-existence and α phase large-angle superposition lattice crystal-boundary was also presented by means of computer programming. The recursion method was adopted to calculate the circumstance sensitivity embed energy of rare earth(RE) and iron in grains, crystal boundaries and phase boundaries, respectively. The calculation shows that RE and iron are more stable in phase boundaries than in grains, which explains the fact that the solution of RE and iron in α phase is small and they are affluent ahead of phase boundary, leading to RE and iron atoms congregating on the crystal boundaries and forming complicated RE-compound.
Key words: rare earth; crystal boundary; recursion method; electronic structure
